Backpack



FIG. 1 is a top, front, right perspective view of a backpack showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof;

FIG. 8 is a top, front, right perspective view of a backpack showing our new design in an open configuration; and,

FIG. 9 is a top, front, right perspective view of a backpack showing our new design in an open configuration.

The broken lines within the shaded areas depict unclaimed stitching. The remaining broken lines depict portions of the backpack that form no part of the claimed design. 

CLAIM The ornamental design for a backpack, as shown and described. 